Brillouin scattering spectroscopy

SAWs can be of the generalized (GSAW) or pseuofo-SAW (PSAW) types. The latter, also referred to as leaky waves, are characterized by the facts that energy radiates into the bulk of the medium and that they experience little attenuation and are thus experimentally observable. This type of wave is especially amenable to analysis by Brillouin scattering spectroscopy. 

Brillouin scattering spectroscopy. The present interest in this acoustic-optical technique and the use of laser sources to generate both types of energy warrant detailed description of the measuring instrument. 

Cummins HZ (1979) Brillouin scattering spectroscopy of ferroelectric and ferroelastic phase transitions. Phil Trans Roy Soc Lond A 293 393-405... 

C. H. Wang Raman and Brillouin scattering spectroscopy of phase transitions in solids. In Vibra- 5.40 tional Spectroscopy of Phase Transitions, ed. by... 

J. E. Sipe. Brillouin Scattering from Rare Gas Crystals A Theory for the Pockels Coefficients . In J. van Kranendonk (ed.), Intermolecular Spectroscopy and Dynamical Properties of Dense Systems—Proceedings of the International School of Physics Enrico Fermi, Course LXXV, North-Holland, Amsterdam, 1980, pp. 430-464. 

Modem enhancement techniques enable the signal-to-noise ratio to be increased by interactions with surface plasmons (33) or surface effects (34). Inelastic tunneling spectroscopy (35), Brillouin scattering (36), and photoacoustic spectroscopy (37) have also been used to explore the vibrational modes in LB films. 

There are a few publications on the use of other spectroscopic techniques such as Brillouin scattering, photoacoustic, and Raman spectroscopy. The primary application of these has been to study the heterogeneities in polymer blends, viz. crystallization or phase separation. 

The self-association of highly polar liquids has been detected by a number of methods including ir spectroscopy (22), Brillouin scattering (23), dielectric polarization (24), H nmr (25), C nmr (26), F nmr (27), and cryoscopy (28). Quite recently. X-ray diffraction studies have conclusively shown that acetonitrile (29) and higher nitriles form clukers in the liquid state (30). 

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